51 Seconds to 500 Microns

[Pascone10]

THere is not enough volume in that hose is what I learned here. Basically all hose are permeable and it is normal for the micron reading to increase. What you want to do is that test I wrote and see what happens. I use that YJ coupling. It is nice but I like having a ball valve in series with the gauge. I made that with some parts from YJ. They also increase in microns as I let it sit there...

[Shur]

Thanks for the order, we had stopped shipping to Canada for awhile. We were getting hit with a lot of fraudulent orders to the tune of over 10K

I think it was a theft ring. We had to shut down. I just opened it again last week.

Thanks for starting that up again.
Cant order right now but funds will be allocated. Eventually.

[radarjones]

doing a job on a six story low rise with fifty flats running three daikin vrv systems and two systems have twinned hp's. has anyone used the rapid evac in this application? hp1 does sixth floor with 16 fan coil heads, hp2 does floors five and four with twinned hp's, and 32 fan coil heads. hp3 is floors three, two, and one with 34 fan coil heads. really curious to see the result using this method for vac down. also, I have read a lot of the posts in this thread and am curious about the vacuum being so rapid that any moisture at all would freeze in the refer lines. the install has been very meticulous due to the system being so sensitive. anyone who has used this on this scale I would really like to hear your feedback. thanks, radar

[jim bergmann]

doing a job on a six story low rise with fifty flats running three daikin vrv systems and two systems have twinned hp's. has anyone used the rapid evac in this application? hp1 does sixth floor with 16 fan coil heads, hp2 does floors five and four with twinned hp's, and 32 fan coil heads. hp3 is floors three, two, and one with 34 fan coil heads. really curious to see the result using this method for vac down. also, I have read a lot of the posts in this thread and am curious about the vacuum being so rapid that any moisture at all would freeze in the refer lines. the install has been very meticulous due to the system being so sensitive. anyone who has used this on this scale I would really like to hear your feedback. thanks, radar

Here is the video.


There is very little chance of freezing any moisture in an a/c application simply due to the mass of the system. Almost no chance. You would have to be doing the evacuation in close to freezing weather.

[Lightning_Boy]

I'm officially impressed with this setup. Used the megaflow kit
twice in the last 2 days and its saved so much time I can barely
Believe it. I' using it with a Crappy worn down yellow jacket 6cfm pump.
Today I pulled a 3.5 ton split system from 760k to 800 microns in 3 minutes,
From there I did two nitro sweeps and settled on a 415 micron vacuum.

All this done in 25 minutes.

My previous best time with core removers and 1/4" hoses was about an hour n change...

[Bill Lee]

How deep a micron level could one expect to reach after doing a compressor replacement for say: (1) a system up to 5 tons and (2) a system of 10 ton capacity? From what I've experienced is that the residual refrigerant in the system will continue to boil off for quiet a while. I've been usin a 4-port manifold and D-C's and a Supco micron gauge. I now have a Blue-vac in hand and Jim's kit on order. I'm looking forward to using this system!!!

[jim bergmann]

It will go a lot faster then using 1/4" hoses, but telling you how long is impossible. There are a lot of things to consider. To be honest, no one knows.

I cannot stress enough thought when a system has residual refrigerant, a nitrogen purge will go a long way toward getting a more accurate vacuum reading. All thermistor gauges are calibrated for a specific test gas, typically air or nitrogen. When gauge sensor is exposed to a refrigerant atmosphere, it effects the calibration and you will not be able to accurately determine the final evacuation level.

[pacnw]

I am going to presume that we are not going to be able to achieve the 51 seconds on a repair call due to refrig, oil &/or moisture in the system, correct?

Your test was on a new install, line set and evap only, correct?

Any levels/readings on micron gauge to indicate specific issues, like "XXXX" is residual "Y" or the like?

[jim bergmann]

I am going to presume that we are not going to be able to achieve the 51 seconds on a repair call due to refrig, oil &/or moisture in the system, correct?

Your test was on a new install, line set and evap only, correct?

Any levels/readings on micron gauge to indicate specific issues, like "XXXX" is residual "Y" or the like?

The video showed a new install, line set and coil. The time shown to reach 500 microns is typical for that application. The system was swept with dry nitrogen, cores removed, large hoses, and a good vacuum pump. When I started thought I could not have told you whether it would have taken 51 seconds to reach 500 microns or 5 minutes. It really depends on how dry the system was kept during the installation. The goal of the video was not 51 seconds, it was to demonstrate how fast a proper evacuation can be done wit the correct tools and procedure.

That being said, if you wee on a compressor replacement with a contaminated line set/system, and out gassing to contend with yes it would take longer, but it would take 1/10 of the time of 1/'4" hoses. So what might take you an hour with 1/4" hoses would take me 6 minutes. Or you 4 hours me 24 minutes. How though long depends on a lot of variables. (And I really mean 1/10th of the time, it is simply physics of vacuum)

Good practice, a nitrogen sweep when things stall, and the right equipment though will make all the difference in the world.

[hvaclover]

Jim, I wish you would include DRY CO2 as a sweep gas as much as you do nitro.

It was used for years before nitro came along. Me and several of my colleagues
all use DRY CO 2. The benefits are many and varied over NITRO.

Heck, if you have a dissenting opinion on DRY CO 2, I'm sure we'd all like to hear it too.

I have been trying to do a video on it, but I can't find the time (Damn, I don't know how the UTubers keep cranking them out and still do service calls).

Whattaya say, Mench?

[jim bergmann]

Jim, I wish you would include DRY CO2 as a sweep gas as much as you do nitro.

It was used for years before nitro came along. Me and several of my colleagues
all use DRY CO 2. The benefits are many and varied over NITRO.

Heck, if you have a dissenting opinion on DRY CO 2, I'm sure we'd all like to hear it too.

I have been trying to do a video on it, but I can't find the time (Damn, I don't know how the UTubers keep cranking them out and still do service calls).

Whattaya say, Mench?

There are a few disadvantages of using CO2 as a sweep gas, but not what you might think.

1) Typical thermistor micron gauges are not calibrated for it and it will impact the reading of the gauge. They are calibrated for air or nitrogen.

2) It is about 1.5 times heaver than air (which is 78% nitrogen) and harder to remove through evacuation.

Aside from that, for removing moisture and pressure testing it should be OK. I used it myself for years but later on found nitrogen a lot better for the application.

[Pascone10]

There are a few disadvantages of using CO2 as a sweep gas, but not what you might think.

1) Typical thermistor micron gauges are not calibrated for it and it will impact the reading of the gauge. They are calibrated for air or nitrogen.

2) It is about 1.5 times heaver than air (which is 78% nitrogen) and harder to remove through evacuation.

Aside from that, for removing moisture and pressure testing it should be OK. I used it myself for years but later on found nitrogen a lot better for the application.

You always amaze me with the info and numbers you post here.. Interesting indeed.

SO lets say with the Blu Vac ( seems like you talk to Joeyd a bit) How much will using CO2 affect the reading. IOW Could I be at 1200 microns and the gauge will read 500. How much does co2 actually influence the reading?

Thanks Jim.

[hvaclover]

There are a few disadvantages of using CO2 as a sweep gas, but not what you might think.

1) Typical thermistor micron gauges are not calibrated for it and it will impact the reading of the gauge. They are calibrated for air or nitrogen.

2) It is about 1.5 times heaver than air (which is 78% nitrogen) and harder to remove through evacuation.

Aside from that, for removing moisture and pressure testing it should be OK. I used it myself for years but later on found nitrogen a lot better for the application.

I don't put the gauge on til I have purged the system. And my OEM said residual CO2 pressure would not affect the reading.One of the first things I asked when I bought my gauge. Guess I got one that can do CO2 as it is not the "typical sort" as you described.
That being said, I am at a loss to reconcile what you are telling me.

Perhaps you could expand a bit into the physics of it. Might make a difference.
Thx